You are here

Reliability of Automatic Sprinkler Systems

The performance results of automatic sprinkler systems was published annually by NFPA up until the 1970s and are often used to quote the expected performance of systems today.

A number of factors in the market since the 1970s, including the increase in the number of fully supervised systems, would be expected to increase the reliability of systems. However, the reliability of systems necessitates the incorporation of what were once insurance factors used to improve system performance in relation to the ?risk?. For instance, large facilities may incorporate looped mains, secondary, tertiary and quaternary supplies with different water sources in combination and prioritised in terms of performance and reliability.
For complex high buildings in Canada some insurers in the 1970s had tabled potential reliability guidelines based on occupancy risk, construction, height and other factors. The aim of the proposed guidelines were to improve system performance with higher buildings and avoid unnecessary impact of failures when systems were highly reliant on pumps.
An interesting factor today is that certain standards which eliminated sprinklers in certain areas such as roofs were designed to make such systems more affordable. Such factors introduce failure modes which ultimately can reduce reliability of systems.
The mandating of sprinkler systems by the NBCC and other bodies, while helping to increase the performance of buildings in response to fires, has no mechanism to address reliability other than system supervision and emergency power in high buildings. The proposed use of timber for tall wood buildings may necessitate the need for a reassessment of sprinkler system reliability.
Jack Mawhinney will look at typical failure modes and investigations of reliability based on failures of actual systems and subsequent forensic investigations.
These investigations throw light on failure modes of systems and potential ways to increase reliability to reduce potential failures.

Jack Mawhinney, P. Eng., FSFPE
Between 1965 and 2015, Jack's career included 19 years in fire protection contracting in B. C., five years as technical advisor to the fire code committees at IRC in Ottawa, six years as a Senior Research Officer at the National Fire Laboratory in Ottawa, and 19 years in the U.S. as a senior engineer involved in fire testing of suppression systems and forensic analysis as an expert witness.